Aerosol hard surface cleaner



United States Patent ()fiiice 3,354,088 Patented Nov. 21, 1967 Thepresent invention relates to an aerosol cleaner which is especiallydesigned for use on hard surfaces. More particularly, it relates to sucha cleaner consisting of a propellant, a cleansing concentrate and asmall amount of an amorphous silica.

Cleaning compositions for difiicult to clean hard surfaces, such asovens, are shown. Typically, such compositions are viscous liquids whichare applied to the surface to be cleaned with a brush, for example.While such compositions are fairly effective cleaners, the procedureemployed in using them involves a certain amount of mess andinconvenience.

More recently, aerosol compositions have come into widespread use. Avariety of having cream compositions are available in aerosol packagesahd even food products, such as dessert toppings, can be purchased inaerosol containers. Cleaning compositions, particularly window cleaners,are also available in this form. The use of aerosols reduces theinconvenience connected with conventional preparation and/r applicationof the various described compositions.

However, merely because aerosol packaging and application have comeintowidespread use does not mean the automatic solution to problemsfaced in any particular field of endeavor. In this respect, theconventional viscous liquid oven cleanerscould not be simply admixedwith a propellant and applied from an aerosol container. The preparationof aerosol hard surface cleaners presents various problems'Thus saidcompositions must have high cleansing'power and still not be'corrosiveto the container or the surface to be cleaned. Additionally, suchcleaners are especially designed for the cleaning. of ovens and the likewhere vertical as 'well as horizontal surfaces are encountered. Wherevertical surfaces are to be cleaned, the cleansing concentrate shouldhave little or no tendency to run off the surface.

It is an object of the present invention to provide a novel aerosol hardsurface cleaner.

Another object of my invention is to provide such a cleaner which hashigh cleansing power, is non-corrosive, foams and, when applied tonon-horizontal surfaces. does notrun off. 'Still another object of theinvention is to provide a 'novel aerosol hard surface cleaner consistingof a propellant, a cleansing concentrate and a small amount ofanamorphous silica. I

These and other objects will become apparent from the following detaileddescription.

I have now discovered that a highly useful aerosol hard surface cleaneris obtained by including a small' amount of an amorphous silica in acomposition otherwise consisting of a cleansing concentrate and apropellant. It was found that the amorphous silica prevents run off ofthe cleansing concentrate from non-horizontal surfaces while other knownflow retarders, such as methyl cellulose, slow the flow of the cleanerbut do not prevent it. i

The cleansing concentrate consists essentially of an amphotericdetergent and a solvent. Especially preferred amphoteric detergents areselected from compounds of the general structural formulae:

RNHCR CR COOX and R'N (CR CR COO) X where R' is hydrogen or a loweralkyl group containing less than four carbon atoms, R is a highmolecular weight, straight or branched chained, hydrocarbon radicalcontaining Sto 22 carbon atoms and X is hydrogen, alkali metal, ammoniumor an alkanol amine such as mono-, dior tri'ethanol amine. X ispreferably hydrogen, sodium, potassium or ammonium. These compounds arereadily available commercial compounds. All may be classified assubstituted products of beta-amino propionate where thehydrocarbonradiacl, R-, is derived from various high molecular weightacids and contains the same number of carbon atoms as the original acid.Common sources of these acids are rosin acids and the fatty acids suchas those obtained from tall oil, soybean oil, coconut oil, cottonseedoil, linseed oil, soapstock, safllower oil, castor oil, tallow, lard,and other fats and oils. It will be appreciated that the acids obtainedfrom each source are generally a complex mixture, which are, for allintents and purposes, relatively uniform in composition. Thus R'- isoften defined according to the source of the original acids, i.e.,cocococonut oil, tallowtallow, rosin-rosin acids, and so forth.

The solvent comprises water, a lower aliphatic alcohol (1-4 carbonatoms) anda liquid hydrocarbon. Representative alcohols are methanol,ethanol and isopropanol with the latter being preferred. Arepresentative and preferred liquid hydrocarbon is odorless mineralspirits.

Keosene can be employed where there is noobjection to the type of odorwhich the cleansing concentrate has. More volatile hydrocarbons can beemployed where no fire hazard is presented. y I In addition to theamphoteric detergent and solvent, the

cleansing concentrate may also contain small amounts of other materialssuch as auxiliary cleaners. A representative and preferred auxiliarycleanser is ammonium hydroxide. Sodium and potassium hydroxide can alsobe used but are less preferred because of their caustic nature. Thusthey present somecorrosion problems and could cause injury if thecleansing concentrate was accidently sprayed in such a manner asto comein contact with the users eyes. Minor amounts of other known detergentscan also be included although generally the amphoteric detergentprovides sufiicient cleansing power. A small amount of glycerine can beincluded to prevent the drying out of the product when sprayed and leftto work for a time before being wiped off.

The propellant may be selected from any of those commonly employed inaerosol compositions. Representative propellants are trifluoro trichloroethane (Freon 113), di-

chloro difluoro methane (Freon 12), tetrafluoro dichloro ethane (Freon114), pentafluoro monochloro ethane (Freon 115 octafluoropropane (Freon218), cyclic octafluorobutane (Freon C-318), propane, isobutane, butaneand the like. Mixtures of various propellants can also be used. Thepreferred propellants are the non-flammable Freons, isobutan'e ormixtures of propane and isobutane.

The amorphous silica is used in an amount sufiicient to prevent run offof the cleansing consentrate upon application thereof on non-horizontalsurfaces. Such amounts will preferably be within the range of about 1 to2% by weight based on the total weight of the ingredients in the aerosolcontainer. The preferred amorphous silicas have a particle size range of.005 to about 0.1 micron. A particularly preferred amorphous silica isCab-O-Sil which has a particle size range of .015-.020 micron. Cab-O-Silhas the following additional properties:

.S iO content (moisture-free basis) percent Surface area (BET-nitrogenadsorption method) sq. m./gram 175-200 Oil absorption (Gardner method)lbs. pigment..- 150/100 The propellant, cleansing concentrate andamorphous silica can be packaged in any of the available pressure-:tight containers having a valve-controlled opening which regulates flowthrough a discharge .conduit leading to the base .of the .container. thesuch container is described in United States Patent 1,892,750. Thecontainer .can (be charged by chilling the mixed ingredients to a.temperature at or below thetemperature at which :the propellant is :inthe liquid phase, introducing the chilled ingredients into the containerand then sealing same. .Of course, the propellant can be introducedseparately and then the con- .tainer can .be sealed, .or the propellantmay be introduced after sealing. This latter procedure :is preferredwhen using the hydrocarbon or low boiling fluorinated hydrocarbonpropellants. The pressure-tight aerosol containers and :the methods ofcharging same are well known and form no part of this invention.

The ratios .of the various ingredients in my aerosol p ckage can varyover relatively wide limits. Thus the propellant .is used in an amountsufficient to evacuate :the contents of the aerosol conta ner and theamorphous silica is used in an amount sufficient .to prevent flow or runoff of the clean ing con entrate when ap 10 1 horizontal urfaces with heremainder consisting of the cleansing concent ate. Taking .into acco ntthe i gredicuts of the cleansing-concen ate, the preferred ratios a e asf llows:

Ingredient- Parts by weight Propellant 4-30 Amorphous silica 1-2Cleansing concentrate:

Amphoteric detergent 2.5-20

Water .s-- ,5-70

Lower aliphatic alcohol 5-20 "Liquid hydrocarbon 2-20 Glycerin -10Auxiliary cleansers 0-10 Especially preferred ratios are as-follows:

Ingredient- Parts by weight Propellant s Amorphous silica 1-2 Cleansingconcentrate:

Amphoteric detergent 2.5- Water 50-70 Lower aliphatic alcohol 7.5-Liquid hydrocarbon v r 2.5-7.5 Glycerin 2.5-7.5 Auxiliary cleanser.1'0-5 The following examples are furnished for the purpose ofillustration only and are not to be construed as placing any limitationon the scope of the present invention.

Example I An aerosol container was charged with the followingingredients:

Ingredient: Parts by weight Propellant (mixture of propane andisobutane) 5 Cab-O-Sil 2 Sodium N-coco fl-aminopropionate 5 Water 67Isopropyl alcohol 10 Odorless mineral spirits ..r 5 Glycerin 5 Ammoniumhydroxide (30%) 1 'When applied as an oven cleaner, the product showedexcellent cleaning action and produced a cleanser foam 0n the ovensurfaces which did not run off to any noticeable extent.

Example 11 Example I was repeated except that methyl cellulose was usedin place of the amorphous silica, Cab-O-Sil. The resulting appliedproduct again had excellent cleaning action but a substantial amount ofthe cleanser foam flowed off .of the non-horizontal surfaces in a fairlyshort time period.

Examples Ill and 1V Example I was repeated except that amorphous silicashaving average particle sizes of 3-5 microns (.Santocel C) and 3.3microns (Syloid 244) were used in place of the Cab-O-Sil. The run offproperties of the cleanser were again unsatisfactory as in Example II.

Example =V Example I is repeated using disodium N-tallow fl-imino-,dipropionate in place of the sodium Necoco p3aminopr.opionate. Equallygood results are obtained. The terms coco and tallow refer .to the factthat the R groups of the said .arnphoteric detergents were derived fromthe fatty acids obtained from cocon oil and tallow, respectively.

Examples VI-VIII Example ,I is repeated using fithyl alcohol in place ofisopropyl alcohol in Example VI and leaving out the glycerine andammonium hydroxide in Examples VII and VIII, respectively. Equally goodresults are obtained with the product ,of Example VI. The product ofExample VII is also excellent but has a tendency to dry out when notwiped off the surface being cleaned in a relatively short time afterapplication. The product of Example V II I has a slightly reducedcleansing action but in other respects is equal to the product ofExample I.

The aerosol hard surface cleaners of the present invenn re useful s ovencleaners. Generally they can'be used as cleaners for metal surfacesglass, ceramics, other non-metallic inorganic surfaces and on hard andrelatively durable organic surfaces such as paint, plastics, linoleumand the like. In addition to their excellent cleansing and non-flowproperties, they are also substantially non- .corrosive and in manyinstances actually function as corros'ion inhibitors.

It is to be understood that the invention is not to be limited to theexact details of operation or the exact processes shown or described, asobvious modifications and equivalents will be apparent to those skilledin the art and the invention is to be limited only by the scope of theappended claims.

I claim:

1. A package consisting of a pressure-tight container having avalve-controlled opening charged with an aerosol hard surface cleanerconsisting of the following ingredients in parts by weight:

Volatile propellant 5-15 Amorphous silica 1-2 Amphoteric detergent 2.5-Water 50-70 Lower aliphatic alcohol 7.5- Liquid hydrocarbon 2.5-7.5Glycerin 2.5-7.5 Auxiliary cleanser .10-5

wherein said amorphous silica has a particle size range of about 0.005to about 0.1 micron, said amphoteric detergent is selected from thegroup consisting of Propellant consisting of a mixture of propane andisobutane Amorphous silica 2 6 Sodium N-coco fi-aminopropionate 5 Water67 Isopropyl alcohol 10 Odorless mineral spirits 5 Glycerin 5 Ammoniumhydroxide (30% aqueous solution) 1 wherein said amorphous silica has aparticle size range of .015 to .020 micron.

References Cited UNITED STATES PATENTS 1,707,031 3/1929 Stuart 252-1392,093,824 9/1937 Woronoff 252-139 XR 2,561,304 7/1951 Hazel 252-313 XR2,913,418 11/1959 Sohngen et al 252163 3,031,408 4/1962 Perlman et al.252-159 XR FOREIGN PATENTS 830,333 3/1960 Great Britain. 572,052 10/1958Belgium.

OTHER REFERENCES John: Modern Polishes and Specialties (1942), Chem.Pub. Co., Inc., pp. 288-289.

LEON D. ROSDOL, Primary Examiner. JULIUS GREENWALD, Examiner.

W. E. SCHULZ, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION November 21, 1967Patent No. 3,354,088

Lyle F. Elmquist It is hereby certified that error appears in the abovenumbered patent requiring correction and that the said Letters Patentshould read as corrected below.

Column 1, line 13, for "shown" read known line 20, for "having" readshaving line 21, for "ahd read and column 2, line. 17, for "radiacl"read line 36, for "Keosene" read Kerosene line 66, for "consentrate"read concentrate column 5, line 7, for "Lower aliphatic alcohol" read HAliphatic monohydric alcohol of 1-4 carbon atoms line 22, after metal,"strike out "and"; same line 22, after ammonium" insert monoethanolamine, diethanol amine, and triethanol amine, and said auxiliarycleanser is selected from the group consisting of ammonium hydroxide,sodium hydroxide and potassium hydroxide line 24, after "aerosol" inserthard Signed and sealed this 17th day of December 1968.

(SEAL) Attest:

EDWARD J. BRENNER EDWARD M. FLETCHER,JR.

Commissioner of Patents Attesting Officer radical

1. A PACKAGE CONSISTING OF A PRESSURE-TIGHT CONTAINER HAVING AVALVE-CONTROLLED OPENING CHARGED WITH AN AEROSOL HARD SURFACE CLEANERCONSISTING OF THE FOLLOWING INGREDIENTS IN PARTS BY WEIGHT: